Cytotoxic T lymphocyte antigen 4 gene polymorphism confers susceptibility to type 1 diabetes in Japanese children: analysis of association with HLA genotypes and autoantibodies.

OBJECTIVE: Although the polymorphisms of the cytotoxic T lymphocyte antigen 4 (CTLA4) gene have been shown to be associated with Type 1 diabetes in Caucasians, some conflicting results have been reported among subjects of different ethnic backgrounds. We examined a CTLA4 polymorphism and its relationship to human leucocyte antigen (HLA) genotypes and autoantibodies for glutamic acid decarboxylase 65 (GAD65) and IA-2 in Japanese children with Type 1 diabetes. SUBJECTS AND MEASUREMENTS: The study group consisted of 125 childhood-onset Japanese subjects (50 males, 75 females) with Type 1 diabetes. The CTLA4 A/G polymorphism at position 49 was analysed using a PCR-restriction fragment length polymorphism (PCR-RFLP) method. The HLA-DRB1 and DQB1 genotypes were defined by DNA analysis using PCR-sequence-specific oligonucleotide (PCR-SSO) probes. The GAD65 autoantibody (GAD65Ab) and IA-2 autoantibody (IA-2Ab) titres were measured using radioimmunoassay. RESULTS: The distribution of genotype frequencies differs between subjects with Type 1 diabetes (GG: 46%, AG: 50%, AA: 5%) and controls (GG: 39%, AG: 44%, AA: 17%) (P < 0.01). The frequency of the G allele is higher in the diabetes group than in the controls (P < 0.05). When the subjects were subdivided according to HLA genotype, the two major HLA high-risk groups, with DR9-DQ9 and DR4-DQ4, that are unique to Japanese populations showed no difference in their CTLA4 polymorphism frequencies. Although no association between the CTLA4 polymorphism and the prevalence of GAD65Ab was found, CTLA4 GG subjects that had been newly diagnosed (< 9 months) had significantly higher levels of autoantibodies than AG subjects (P < 0.01). The prevalence and titres of IA-2Ab were not associated with the CTLA4 polymorphism. CONCLUSIONS: The CTLA4 gene might confer a susceptibility to childhood-onset Type 1 diabetes in the Japanese population. The association between this CTLA4 polymorphism and the HLA genotype was similar for both major groups with HLA high-risk alleles. CTLA4 might contribute to the humoral immune response to GAD in newly diagnosed subjects.

Maternal hypothyroidism in autoimmune thyroiditis and the prognosis of infants.

We evaluated the developmental prognosis of 31 infants born to mothers with autoimmune thyroiditis. Four of the babies developed transient neonatal hypothyroidism. Their mothers all had low thyroid hormone concentrations during pregnancy. Neonatal thyroid function tended to correlate with maternal thyroid function at delivery in babies born to mothers with Graves'disease who were taking antithyroid drugs. Since severe fetal hypothyroidism sometimes results in neurological damage, it is important to maintain normal maternal thyroid function during pregnancy.

Estrogen secreting adrenal adenocarcinoma in an 18-month-old boy: aromatase activity, protein expression, mRNA and utilization of gonadal type promoter.

We examined clinical, endocrinological and molecular biological aspects of an estrogen-secreting adrenal carcinoma in an 18-month-old male to clarify the pathogenesis of this condition. An 18-month-old boy was referred for evaluation of progressive bilateral gynecomastia and appearance of pubic hair. The patient had elevated plasma estradiol (349 pg/ml) and testosterone (260 ng/dl) levels that completely suppressed FSH and LH levels, and was subsequently diagnosed with an adrenal tumor on the right side. After removal of a 300-g adenocarcinoma, gynecomastia regressed and essentially normal hormone levels were restored. Aromatase activity in the tumor tissue determined by the 3H-water method was 71.0-104.4 pmol/min/mg protein. High levels of aromatase protein and mRNA in the tumor tissue were also demonstrated, while neither aromatase activity nor protein was detected in normal adrenal glands. To investigate the regulation of aromatase expression in the adrenal carcinoma, we examined the usage of alternate promoters responsible for aromatase gene transcription. In the present case, the amounts of aromatase mRNA utilizing gonadal types of exon 1c (1.3) and 1d (II) were significantly higher than those that using other exon 1s. This result suggested that the utilization of a gonadal-type exon 1 might be involved in the over-production of aromatase in estrogen-secreting adrenal carcinoma.

Outcome of a baby born from a mother with acquired juvenile hypothyroidism having undetectable thyroid hormone concentrations.

We report a baby born from a mother with strongly positive thyroid stimulation blocking antibody (TSBAB) and nearly undetectable T4 level. This case is a unique model of nearly complete absence of thyroid hormones during fetal and early neonatal life in humans. The infant girl was born by cesarean section, because of fetal bradycardia, after 41 weeks gestation and received mechanical ventilation for 3 days. The TSH level was more than 120 microU/mL in the neonatal thyroid screening. At age 17 days, the results of a thyroid function study showed undetectable free T3 and free T4 concentrations, TSH 550 microU/mL, and TSH receptor antibody (TRAB) 87%. Thyroxine at a dose of 30 microg/day was started at age 17 days. The patient required thyroxine treatment until age 8 months. The brain magnetic resonance image at age 2 months revealed reduced brain size. Her auditory brain stem response was absent at age 2 months. The audiogram at age 4 yr revealed sensorineural deafness of 70 dB. When she was 6 yr of age, motor development remained the same as that at age 4 months. Her height was 106 cm (- 1.5 SD). The results of thyroid function study of the mother 23 days after delivery showed undetectable free T3 and free T4, TRAB 84%, and TSBAB 83%. In conclusion, the outcome of severe thyroid hormone deficiency in utero and early in human neonatal life was normal physical growth, fetal distress resulting in cesarean section, difficulty in the onset of breathing, permanent deficit in auditory function, brain atrophy, and severely impaired neuromotor development despite the start of an adequate dose of thyroxine replacement during the neonatal period.

Association of HLA-DR, DQ genotype with different beta-cell functions at IDDM diagnosis in Japanese children.

Japanese IDDM patients have been demonstrated to have unique and different HLA associations from white patients. To elucidate the effect of HLA-associated genetic factors on the clinical heterogeneity of IDDM in Japanese people, HLA-DRB1, DQA1, and DQB1 genotypes in 88 childhood-onset Japanese IDDM patients were examined by polymerase chain reaction-sequence-specific oligonucleotide (PCR-SSO) or sequence-specific primers (SSP). Of the 88 IDDM patients, 26 (29.5%) had DRB1*0405-DQA1*0302-DQB1*0401/X (DR4-DQ4/X), 38 (43.2%) had DRB1*0901-DQA1*0302-DQB1*0303/X (DR9-DQ9/X), and 9 (10.2%) were DR4/9-DQ4/9 heterozygous in the present study (X does not contain protective alleles). Clinical heterogeneity such as age distribution at onset, prevalence and serum level of anti-GAD antibodies (GADAb), and residual pancreatic beta-cell function after diagnosis were compared between patients with HLA-DR4-DQ4 and DR9-DQ9. The frequency of DR9-DQ9 genotype was significantly higher in the younger (0-10 years) than in the older (11-16 years) age-group of onset, but the frequency of DR4-DQ4 was higher in the older (11-16 years) age-group. Although no association of DR-DQ genotypes with the prevalence and serum level of GADAb was found among newly diagnosed patients, long-standing DR9-DQ9 patients had significantly higher levels of GADAb than those with DR4-DQ4. While no difference in time course of serum C-peptide (CPR) levels was detected between GADAb+ and GADAb- patients, a remarkable difference was demonstrated between DR9-DQ9 and DR4-DQ4 patients. The residual pancreatic beta-cell function was retained more in patients with DR4-DQ4 than in those with DR9-DQ9 at diagnosis through 12-18 months after diagnosis. These results suggest that the DR9-DQ9 genotype may induce stronger autoimmune destructive response (T-helper 1 function) against target beta-cells than the DR4-DQ4 genotype does. Our findings may warrant further studies on the association of diabetogenic autoimmune response with HLA class II molecules and contribute to a clarification of interracial differences in HLA-encoded susceptibility to IDDM.

Clinical significance and time course of antibodies to glutamic acid decarboxylase in Japanese children with type I (insulin-dependent) diabetes mellitus.

Although anti-glutamic acid decarboxylase antibodies (GADAb) have been reported to be a useful diagnostic and predictive marker of insulin-dependent diabetes mellitus (IDDM, type 1 DM) in Caucasians, a precise analysis of GADAb in Japanese children has not been reported. We examined the clinical significance and time course of GADAb in Japanese IDDM children, who have different genetic backgrounds from Caucasians. Twenty-three of 34 (67.6%) sera from recent-onset (< 6 months) IDDM, and 16 of 49 (32.7%) sera from long-standing (> or = 2 years) IDDM patients were positive for GADAb. This prevalence of GADAb in IDDM patients was significantly higher than in normal controls and the other groups including non-insulin-dependent DM, autoimmune thyroid disease and congenital hypothyroidism, and was also significantly higher in recent-onset than in long-standing IDDM. Time course analysis suggested that autoimmune response against GAD could follow different courses in individual cases after the initiation of insulin therapy. The incidence of GADAb was significantly higher in females than in males in the older age group (11-15 years). Other clinical features including residual pancreatic beta-cell function after diagnosis were demonstrated to be similar between GADAb-positive and -negative patients. In conclusion, this study using the newly established radioimmunoassay (RIA) for GADAb revealed a high prevalence of autoimmune reactivity to GAD in Japanese IDDM children. These results, using this RIA procedure, might assist in laying the groundwork for future trials of immunomodulation therapy for IDDM in Japan.

[Clinical study of 15 children with acute suppurative thyroiditis].

From 1969 to 1990, 15 children with acute suppurative thyroiditis (AST) were diagnosed in our hospital. Their clinical, laboratory and radiologic findings were reviewed. The characteristic features were as follows: 1) Males to female ratio was 1.5:1. 2) The ages at diagnosis ranged from 3 to 14 years, with a mean age of 6 years. 3) A painful, tender mass in the anterior neck was detected in all cases and fever was detected in 10 cases (67%). 4) The left lobe of the thyroid was affected in 11 cases (73%), whereas the right lobe was affected in the remaining 4 cases. No cases was bilateral. 5) Five cases (33%) were found to be recurrent. 6) Eight pathogenic organisms were identified on culture from 7 cases; among them 3 were due to anaerobic pathogen. 7) Leukocytosis was increased and acute-phase reactant tests were positive in most cases. 8) Thyroid function was found to be normal in all 9 cases examined. 9) Radiologic studies, which included radionuclide thyroid scan, ultrasonography, computed tomography and barium esophagogram, were very helpful for the diagnosis of AST. 10) A barium esophagogram was performed in 9 cases and a fistula originating from the pyriform sinus was found in 4 cases (44%). 11) Three cases (20%) had the complete removal of the fistula as a permanent cure. This report summarizes the clinical features of 15 children with acute suppurative thyroiditis diagnosed in our hospital during the past twenty years.

Attainment of normal height in severe juvenile hypothyroidism.

Prolonged juvenile hypothyroidism results in a permanent loss in height that is related to the duration of thyroxine deficiency before adequate thyroxine replacement treatment. A 13 year old girl with severe juvenile hypothyroidism was studied prospectively. She had an undetectable serum thyroxine concentration, a height SD score of -6.6 SD, and a bone age of 5.8 years. The enlarged pituitary gland involuted with thyroxine treatment to produce an empty sella. In addition to thyroxine the girl was treated with a gonadotrophin releasing hormone agonist to avoid the progression of puberty for 18 months and with growth hormone to achieve normal adult height.

Suppression of sex steroids by a gonadotrophin-releasing hormone agonist increases serum growth hormone-binding protein activity in girls with central idiopathic precocious puberty.

OBJECTIVE: The high-affinity growth hormone (GH)-binding protein corresponds to the extracellular domain of GH receptor. The direct role of sex steroids in pubertal bone growth may be an increased GH receptor-coupled GH action. We examine the GH-binding protein (GHBP) activity before and after the suppression of female sex steroids and the relation of GHBP to pubertal growth. PATIENTS: We studied six girls with central idiopathic sexual precocity without any prior gonadal suppression therapy. DESIGN: We measured GHBP activity before and 12, 24 and 48 weeks after the treatment with s.c. injection of a GnRH agonist (leuprolide acetate) every 4 weeks. MEASUREMENT: GHBP activity was measured by immunoprecipitation using anti-GH receptor monoclonal antibody. RESULTS: The treatment caused a decrease in the LH and FSH responses to GnRH test and plasma oestradiol, which resulted in decreased urinary GH excretion, plasma IGF-I levels, height velocity and bone age maturation. GHBP activity before the start of the treatment was normal (75 +/- 27% relative to adult pooled serum, mean +/- SD), and it was increased above adult level (122 +/- 29% at 48 weeks, P < 0.01) by the suppression of the pituitary-gonadal axis. There were significant negative correlations between GHBP and oestradiol (r = 0.452, n = 24, P < 0.05) and between GHBP and urine GH excretion (r = -0.462, n = 24, P < 0.05). CONCLUSIONS: The high-affinity GHBP is increased by the withdrawal of female sex steroid. The clinical significance of this finding may be interference with the binding of GH to its receptor resulting in a reduced IGF-I level and decreased height velocity. The mechanism warrants further study.

Demonstration of cells with Marek's disease tumor-associated surface antigen in chicks infected with herpesvirus of turkey, O1 strain.

The presence of Marek's disease tumor-associated surface antigen (MATSA) was demonstrated by the direct and indirect membrane immunofluorescent tests, in chicks inoculated 7-10 days earlier with herpesvirus of turkeys (HVT), O1 strain. In in vitro cultures of spleen lymphocytes and ovaries obtained from these chicks, MATSA-positive cells were also detected after 1-7 days cultivation. A possible mechanism of protection by HVT vaccine against Marek's disease is proposed.